Venous Thromboembolism Prophylaxis - Why Should We Care? Harry Gibbs FRACP FCSANZ Vascular Physician The Alfred Hospital

Venous Thromboembolism Prophylaxis - Why Should We Care? Harry Gibbs FRACP FCSANZ Vascular Physician The Alfred Hospital

VTE is common and dangerous

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VTE is Common VTE Incidence: 1.5 / 1000 per year 2/3 DVT; 1/3 PE Prevalence of 1% by age 40 years

PE is Dangerous Pulmonary embolism 25% sudden death 5% further 7 day mortality with anticoagulation 30% 1 week mortality

All autopsies at University of Michigan Medical Center from 1964 to 1974 70% autopsy rate; 4600 autopsies Relationship to Death PE found in 12.3% Sole immediate cause 4.4% Contributory 2.7% Minor 5.3%

DVT is Dangerous Post thrombotic syndrome 60% following symptomatic DVT 10% with disabling symptoms 4% develop venous ulcers

VTE Treatment is Dangerous 3 months of anticoagulation for provoked VTE LMWH or UFH followed by warfarin Major bleeding in 5% Inconvenient Costly

VTE Cases 14716 Working age 43% Deaths 5285

Access Economics 2008

VTE is Common and Dangerous Pulmonary embolism most deaths occur before treatment can be started Post thrombotic syndrome high incidence in spite of anticoagulation Treatment Potentially dangerous and difficult VTE prevention is the only way to reduce its complications

VTE is Preventable

VTE prophylaxis Identify those at risk and prescribe prophylaxis for them

VTE Attributable Risk Spencer Arch Int Med 2007 Heit Clin Chest Med 2003

Risk Factors for VTE Disease or surgery related Patient related Risk factors are additive

Surgical VTE Rates Incidence of symptomatic venous thromboembolism after different elective or urgent surgical procedures White Thromb Haemost 2003 1,653,275 cases undergoing 76 different surgical procedures 3 month rate of VTE recorded

Symptomatic VTE in Surgery Procedure Lower limb embolectomy or endarterectomy VTE Rate 2.8% Hip arthroplasty 2.4% Invasive neurosurgery 2.3% Knee arthroplasty 1.7% 56% of VTE cases occurred after hospital discharge White Thromb Haemost 2003

VTE and Malignant Surgery Procedure VTE Rate Radical cystectomy 3.7% Invasive neurosurgery 3.6% Hip arthroplasty 3.1% Internal fixation femur 3.0% Partial hip arthroplasty 2.8% Permanent colostomy 2.6% White Thromb Haemost 2003

Disease Related Risk Factors Condition VTE rates Active cancer 60% Stroke 56% Decompensated heart failure 26% Myocardial infarction 26% Acute respiratory disease 25% Acute rheumatic disease 20% Acute infectious disease 16% Myeloproliferative disorders? Inflammatory bowel disease?

Patient Related Risk Factors Risk Factor Odds ratio Prior VTE 15 Immobilisation 6 Varicose veins 5 OCP / HRT 3 Obesity 2 Advanced age 2

VTE and Hospitalisation VTE is a common complication of hospitalisation Hospitalisation is the commonest cause of VTE VTE prevention should be optimised during hospitalisation

VTE Prevention VTE is preventable Prophylaxis reduces VTE

VTE Prophylaxis Types of prophylaxis Pharmacological Aspirin Graduated compression stockings Unfractionated heparin Intermittent pneumatic compression Low molecular weight heparin device Warfarin Foot compression device Danaparoid Lepirudin Fondaparinux Rivaroxaban Dabigatran Apixaban Mechanical

Efficacy of Anticoagulant Prophylaxis Collins R, et al. N Engl J Med 1988,318:1162-73.

Efficacy of GCS

Goals Risk assess all adult, medical and surgical acute care patients Prescribe appropriate prophylaxis

First the patient must recover from the disease, then he must recover from the medicine - Osler

Appropriate Prophylaxis Prescription of prophylaxis appropriate to patient risk, and presence of contra-indications

Appropriate Prophylaxis High risk surgical Anticoagulant and mechanical, or Anticoagulant if contra to mechanical, or Mechanical if contra to anticoagulant, or Nothing if contra to anticoagulant and mechanical High risk medical Anticoagulant, or Mechanical if contra to anticoagulant, or Nothing if contra to anticoagulant and mechanical

Study Population Number Baseline audit 4399 Post intervention audit 4375 Total 8774

Appropriate Prophylaxis In High Risk Patients Appropriate Prophylaxis Baseline 38% Post intervention 54% Absolute improvement 16% (12 21%) p <0.001

There are more things in Heaven and Earth, Horatio, Than are dreamt of in your philosophy

There is a lot more to understand and do

Some Challenges Better risk identification?genetic testing?racial differences?biomarkers?other things

VTE In Asia Racial differences may exist due to Differences in the incidence of VTE Differences in the risk of bleeding Due to Genetic, Dietary, Environmental and/or Social factors

Bleeding In Asians Higher rate of bleeding with warfarin VKORC1 polymorphism More bleeding with heparin for PCI in Asians

Am J Cardiol 2010

Jupiter 17802 healthy subjects LDL <3.4 and elevated CRP Randomised to rosuvastatin or placebo Median follow-up 1.9 years

Jupiter Rosuvastatin Placebo HR Unprovoked VTE 0.18 0.32 0.57 Provoked VTE 0.10 0.17 0.61 All VTE 0.08 0.16 0.52

Novel Risk Factors Depression Body height Leg length Diet Coffee

25,964 subjects aged 25-96 years Enrolled 1994-5; followed to 2007 VTE incidence 1.56 / 1000 per year HR Often depressed 1.59 (1.01-2.49) Often happy 0.60 (0.41-0.88) Often lonely 1.29 (0.77-2.15)

VTE - Why should we care Common and dangerous Preventable The challenge to improve knowledge and practice